Transformer mounting



Jan. 11, 1949. w. H. GILMAN 2,459,023

TRANSFORMER MOUNTING Filed Sept. 27, 1946 in J INVENTOR. WAYNE H. GILMAN ATTORNEYS Patented Jan. 11, 1949 TRANSFORMER MOUNTING Wayne H. Gilman, Oak Park, 111., assignor to Per noflux Corporation, Chicago, 111., a corporation of Illinois Application. September 27, 1946'. Seth- N 0.. 699.921

(01. ire-35s giclalms.

This invention relates to. mounting of trans.- formers in their position of use, as for example upon the yoke of a loud speaker or the like.

In the manufacture of loud speakers for use in radios or public address systems it is customary to permanently associate an impedance matching transformer with the speaker as by mounting the transformer upon the magnetic yoke of the speaker. Such transformers are usually manufactured with a mounting frame in the form of a channel-shaped member that embraces three sides of the, rectangular pack of laminations of the transformer in such a way that the free ends of the mounting frame. project beyond the other edge or side of the laminations to afford ears for use in securing the transform-- rectangular plate, fixed as by welding to the yoke.

of the speaker, and against which the exposed'side of the laminations is positioned when the transformer is finally mounted. The mounting plate has been provided with narrow projecting lugs centrally disposed on opposite ends thereof in position to be extended through and interlocked with transverse slots formed in the respective ears of the mounting frame. In thus mounting the transformer it has been necessary, to bend one or both of the side members away from the laminations in order to enable the lugs of the mounting plate to pass through the slots in the respective ears of the mounting frame, and after bending the frame back into position with the lugs passing through the slots, it has been customary to bend the lugsso as to en a e the outer faces of the ears, thereby to lock the sides of the frame in position. Such mounting of a. trans.- former in position on the yoke of aloud speaker has been considered to be objectionable, primarily because of the uncertainties that are introduced by reason of the required outward bending and disturbance of the sides of the mounting frame. It will be recognized that transformers that are used for matching purposes must have.

predetermined electrical characteristics, and such transformers are normally manufactured tested by companies that specialize in transformer work. Thus, the electrical characteristics of the transformer are determined and tested while the mounting frame is in place on the transformer, and when it becomes necessary to disturb. the relationship of this metallic mounting frame with respect to the laminations of the transformer, there is danger that the electrical characteristics of the transformer may be objectionably modified. It is, therefore, an important object of the present invention to enable transformers to be mounted in position on the yoke of the loud speaker Without disturbing the relationship. of the mounting frame to the laminations of the transformer, and a related and more specific object of the invention is to enable such mounting tobe simplified so as to eliminate manual operations that have heretofore been required. A further object of the invention is to enable such transformers to be mounted in positionand fixed in such position by operations that involve bending of only those parts of the mountingframe which are not in contact with the 1aminations of the transformer. More specifically, it is an object of the present invention to enable such atransformer to be quickly moved into the desired position with relation to the yoke of the transformer and to enable the transformer to be fixed. in position readily and easily and without disturbance of the relationship of the mounting frame with respect to the laminations of the transformer.

Otherand further objects of the present invention will be apparent from the following description. and claims and are illustrated in the accompanying drawings which by way of illustration, show a preferred embodiment of the present invention and the principle thereof and what I now consider to be the best mode in which I have contemplated applying that principle. Other embodiments of the invention embodying the same or equivalent principles may be used and structural changes may be made as desired by those skilled in the art without departing from the present invention and the purview of the appended claims.

In the drawings:

Fig. l is a perspective view of a transformer mounted in accordance with the present invention;

Fig. 2 is a perspective view showing the transformer and the mounting bracket in the relation in which they are disposed just prior to assembly;

3 is afragmentar-y side elevational view of he a se y:

of course be of any usual construction but as herein shown includes a body or pack of laminations is through and about which the primary H and secondary coils are wound as indicated generally at it in the drawings. The laminations l3 are generally rectangular in external form, and extend outwardly beyond the outside of the windings M, and for the dual purpose of-holding the J laminations it together and for securing the transformer in position as for example on the yoke I i, the transformer H] has a mounting frame 55 disposed in an embracing relationship about three sides of the rectangular pack of laminations. The mounting frame I is made from a relatively thin sheet metal that is channel-like in cross section, as shown in Fig. 5 of the drawlugs, and this channel has flanges A formed along its edges so that the channel may snugly embrace the edge portion of the laminations l3, as shown in Fig. 5. The flanges I5A are notched at the MN at the points where corners are to be formed, thereby to enable the frame IE to be bent' to the generally U-shape form as will be evident in Fig. 1 of the drawings, and the three-sided mounting frame !5 that is thus afforded is disposed in an embracing relationship with respect to the laminations so that the channel form of the frame embraces three sides of the pack I3 of laminations. At the ends of the frame, the channel member extends beyond the face or edge i333 of the laminations to thereby provide ears I5E,

and the end portions of the flanges I5A are in each end cut away as in i 5C so as to simplify the use of the ears i5E in the mounting operation.

In accordance with standard practice in the art, the ears 55E have transverse slots formed therein so that these slots are disposed with the lower edges EilL thereof disposed somewhat below the lower edge surface |3B of the laminations.

In the past the slots 20 have been utilized to re- J ceived fastening ears or lugs that were integral with a fixed or stationary member upon which the transformer was to be mounted, and such lugs were, of course, so spaced that in order to engage the lugs with the slots 20 of the mounting frame of the transformer, it has been necessary to bend one or both of the side elements of the frame :15 in an outward direction away from the laminations of the transformer. Thus, these side members of the frame i5 have been bent outwardly along the lines or pivots I5P in an amount sufficient to enable the transformer to be moved into position with the mounting lugs in alignment with the slots 20, after which the side members of the frame have been ,bent back into' position so that the mounting lugs project through the slots 28, and the lugs were thereafter bent so as to hold the side members of the frame IS in engagement with the mounting lugs.

The construction of the transformer I0 and the mounting frame i5 as hereinabove described has been standard in the transformer industry for many years, and during this time it has been recognized that the separation of the side members of the channel from the laminations in the course of the mounting operation constituted an objectionable practice because of the tendency to alter the electrical characteristics of the transformer. One factor in altering the electric characteristics has been the release of the laminations l3 which are held together by the flanges 15A of the frame, while another factor has been the changein the relationship of the web of the channel with respect to the edges of the laminations.

Under the present invention, the transformer 16" of the aforesaid standard construction is mounted in position on a magnetic yoke l I or the like Without the necessity for separating or otherwise disturbing the side members of the frame I5.

In accomplishing this advantageous result, a

mounting plate made from metal and substantially rectangular in form is secured as by spot welding at 25A to the side surface of the yoke ll.

' The mounting plate 25 has end edge surfaces 25E that are spaced apart in an amount equal to the space between the inner surfaces of the ears I5E, and on each end of the mounting plate 25 a pair of spaced mounting lugs 25L is provided so as to project endwise from the end edge 25E of the plate. The lugs 25L are spaced apart in a distance that is substantially equal to the width of the ears I'BE of the mounting frame so that the ears 325E may be moved downwardly, as viewed in Fig. 2, into the spaces between the pairs of ears 25L. When this is done, the inner faces of theears are disposed in abutment with the end surfaces 25E of the mounting plate 25, while the lugs 25L extend past the opposite edge surfaces of the ears l5E. This preliminary assembly operation is, of course, performed without disturbing the relationship of the side members of the frame 25 with respect to the laminations l3, and hence the electrical characteristics of the transformer are not disturbed in any way.

After the aforesaid preliminary operation has been performed, the lugs 25L and the ears [5E are interlocked so as to hold the transformer in position on the mounting plate 25. In this connection, it should be noted that the formation of the slot 20 in the ear l5E affords a transverse securing bar 20B disposed between the edge 20L of the slot 20 and the lower end of the ear I51], and

this mounting bar is utilized in securing the transformer H] in position.

1 also bent into an engaging relation as will be evident in Figs. 1, 3 and 4, and in this operation the lugs 25L 'at each end of the plate 25 are bent inwardly so as to overlie the outer faces of the ears 15E. This prevents movement or displacement of the side members of the frame l5 in an outward direction away fromthe end edges 25E of the mountingplate. Hence, the lugs 25L insure that the securing bars 20B will be held in their interlocked-position beneath the lower face of the It should be observed that the bending of the securing bar 26B to its arcuate form'tends to draw the side edges of the ear 15E together, 'a's'will be evident in Fig, 3 of the drawings, and because of this, it is preferable to per- :cfo'ririj thejbending operation upon the bars 203 eitherprio'r to or simultaneously with the clinching of the lugs 25L, for by such procedure the engagement of the lugs 25L firmly with the side edges of the ears |5Eis assured.

From the foregoing description it will be evident that the present invention materially simplifies the mounting of electrical transformers in fixed positions on loud speakers or the like, and it will also be clear that the mounting of the transformer is accomplished under the present invention without disturbance of the electrical characteristics of the transformer. The mounting of the transformer under the present invention is also advantageous in that the mounting operations are simplified and may be more readily performed by purely mechanical means.

Thus, while I have illustrated and described the preferred embodiment of my invention, it is to be understood that it is capable of variation and modification and I, therefore, do not wish to be limited to the precise details set forth, but desire to avail myself of such changes and alterations which fall within the purview of the following claims.

Iclaim:

1. In a transformer mounting, a transformer having rectangular laminations with exposed edges, a three sided mounting frame of channelshaped cross section embracing threesides of the exposed laminations and embodying securing ears at the ends of the frame extending beyond the fourth side edge of said laminations, said securing ears having transverse slots formed therein so as to define transverse securing bars at the ends of said cars, a mounting plate having a pair of spaced lugs formed at each end thereof, said transformer being disposed on said plate with said fourth side edge of said laminations abutting one face of said plate and with the ears of said frame extending respectively between the pairs of lugs at opposite ends of said plate, said lugs being bent inwardly toward each other and over the related ears to hold the same against the ends of said plate and said securing bars being bent arcuately beneath the opposite face of said plate to hold said ears in position between said lugs.

2. In a transformer mounting, a transformer having rectangular laminations with exposed edges, a three sided mounting frame of channelshaped cross section embracing three sides of the exposed laminations and embodying securing ears at the ends of the frame extending beyond the fourth side edge of said laminations, said securing ears having transverse slots formed therein so as to define transverse securing bars at the 1.;

ends of said cars, a mounting plate the opposite ends of which are spaced apart a distance equal to the length of said fourth side of said laminations and said plate having a pair of spaced lugs formed at each end thereof with the lugs of each pair spaced apart a distance equal to the width of said ears, said transformer being disposed on said plate with said fourth side edge of said laminations abutting one face of said plate and with the ears of said frame extending respectively between the pairs of lugs at opposite ends of said plate, said lugs being bent inwardly toward each other and over the related ears to hold the same against the ends of said plate and said securing iii) bars being bent arcuately beneath the opposite face of said plate to hold said ears in position between said lugs.

3. In a transformer mounting, a transformer having rectangular laminations with side edges and having mounting means thereon including securing ears disposed at the ends of and es tending beyond one side edge of said lamination said securing ears having transverse slots formed therein so as to define transverse securing bars at the ends of said ears, a mounting plate having a pair of spaced lugs formed at each end thereof, said transformer being disposed on said plate with said side edge of said laminations abutting one face of said plate and with the ears of said frame extending respectively between the pairs of lugs at opposite ends of said plate, said lugs being bent inwardly toward each other and over the related ears to hold the same against the ends of said plate and said securing bars being bent arcuately beneath the opposite face of said plate to hold said ears in position between said lugs.

4. In a transformer mounting, a transformer having rectangular laminations with exposed edges, a three sided mounting frame of channelshaped cross section embracing three sides of the exposed laminations and embodying securing ears at the ends of the frame extending beyond the fourth side edge of said laminations, a mounting plate having a pair of spaced lugs formed at each end thereof, said transformer being disposed on said plate with said fourth side edge of said laminations abutting one face of said plate and with the ears of said frame extending respectively between the pairs of lugs at opposite ends of said plate, said lugs being bent inwardly toward each other and over the related ears to hold the same against the ends of said plate and said ears having portions thereof bent into position beneath the opposite face of said plate to hold said ears in position between said lugs.

5. In a transformer mounting, a transformer having laminations with exposed side edges and having spaced securing ears extending beyond one side edge of the laminations, a mounting plate having a pair of spaced lugs formed at each end thereof, said transformer being disposed on said plate with said one side edge of said laminations abutting one face of said plate and with said ears extending respectively between the pairs of lugs at opposite ends of said plate, said lugs being bent inwardly toward each other and over the related ears to hold the same against the ends of said plate and portions of said ears being bent beneath the opposite face of said plate to hold said ears in position between said lugs.

WAYNE H. GILMAN.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,524,591 Starr Jan. 2'7, 1925 2,164,634 Barrett July 4, 1939 

